/Engine/Source/Runtime/Engine/Public/CollisionQueryParams.h
To do this, use ECC_TO_BITFIELD to convert to bit field i.e.FCollisionObjectQueryParams( ECC_TO_BITFIELD(ECC_WorldStatic) | ECC_TO_BITFIELD(ECC_WorldDynamic) )
FCollisionObjectQueryParams ( int32 InObjectTypesToQuery )